SIP: multiple DTMF modes parallel


ich have a SIP service provider that offer DTMF as inband and rfc2833 and I want to use a IVR.

Both alone works perfekt, with dtmfmode=auto / dtmfmode=rfc2833 I get most DTMF digits. But when somebody with a analog phone or a SIP client with “audio”/“inband” calls me, the DTMF digits are not detected. With dtmfmode=inband analog and DTMF-audio callers can use can use DTMF and Asterisk detects the digits. But all callers without DTMF-audio, the rfc2833 and rfc4733 callers can’t use DTMF. Means: Both work perfekt, but only inband or rfc2833 and not both together.

I searched a long time but I don’t find a solution, my first idea was to bridge the call to multiple channels and detect the different types of DTMF manual, but that is very difficult.

Is there a solution to detect digits from multiple DTMF-types? Is that not the default?

Perfekt would be, when it would be possible to write the different DTMF-types to different variables (like that):


Many posts report double detection, it would be perfect when double detection would be possible.and both readable to different variables. Any ideas?


Version: Asterisk 13.13.1
relaxdtmf = yes
rfc2833compensate = yes